The SCB ordered three types of Engerth locomotives for express, passenger and freight service. The express locomotive was the Eb 2/4 that had two driving axles at the front with a wheel diameter of 1,525 mm and a two-axle supporting tender. The cylinders and valve gear were on the inside of the frames. Originally built for wood firing, they were converted to coal firing in 1859 and got a new chimney. After the twelve built at Esslingen in 1857, the SCB bought another identical locomotive from a private operator in 1861. Four more were built in 1872 with a new boiler that had already been fitted to the earlier locomotives.

With later rebuilds, they got a basic cab and starting in 1884, they were fitted with air brakes. In 1891 and 1893, the SCB ordered two other types of locomotives which were designated Eb 2/4. Withdrawals started in 1888 and in 1902, when the SCB became part of the SBB, two were remaining which were withdrawn in 1903 and 1904. The remains of the first locomotive, No. 15 “Speiser”, were used for building the replica of the D 1/3 “Limmat”.